The audio system is disabled when it is disconnected from the power source, such as when the battery is disconnected or goes dead. In certain conditions, the system may display a code entry screen. If this occurs, reactivate the audio system.
Reactivating the audio system
1. Turn the ignition switch to ON *1.
2. Turn on the audio system.
3. Press and hold the audio system power button for more than two seconds.
The audio system is reactivated when the audio control unit establishes a connection with the vehicle control unit. If the control unit fails to recognize the audio unit, you must go to a dealer and have the audio unit checked.
Honda Civic Owners Manual. Automatic Power Off
If you leave the vehicle for 30 to 60 minutes with the shift lever in P*1 and
the
power mode in ACCESSORY, the vehicle automatically goes into the mode similar to
VEHICLE OFF (LOCK) to avoid draining the battery.
When in this mode:
Except U.S. continuously variable transmission models
The s ...